Among indoor units of air conditioners having an air filter at an air inlet, those provided with a dust removing unit for removing dust trapped on the air filter have been known. An indoor unit of this type includes a container box for containing the removed dust, and a user needs to detach the container box to dispose of the dust. However, since the indoor unit of this type is generally installed at high elevations in a room, the detaching/attaching of the container box is burdensome particularly for elderly people and women.
To solve this problem, for example, Patent Document 1 proposes an air conditioner having a function of automatically discharging the dust removed from the air filter out of the indoor unit (to the outside of the room).
Specifically, the air conditioner of Patent Document 1 includes an indoor unit containing a dust removing unit (a dirt removing box) for removing the dust on the air filter. An outdoor unit contains a dirt collecting box and a vacuum suction fan. The dirt removing box in the indoor unit and the dirt collecting box in the outdoor unit are connected through a dirt transfer pipe. In this air conditioner, the dirt (dust) is removed from the air filter by the dirt removing box, and the dirt is sucked into the dirt collecting box by the vacuum suction fan. Thus, the dirt trapped on the air filter can be discharged outside the unit without any troubles to users.
[Patent Document 1] Published Unexamined Patent Publication No. 2004-301363